Being high-power automotive engines, internal combustion engines of this type are widely used in practice. The power of the internal combustion engine is increased by supercharging, i.e. by compressing the fresh air before it enters the cylinder. However, this compression stage simultaneously causes the charge air to become hot, thus exposing the internal combustion engine to thermal stress. It also has a detrimental effect on the exhaust gas temperature and hence on NOx emissions and fuel consumption. For this reason, the air delivered to the cylinder banks is cooled before it enters the intake manifolds as a rule, which can be done using external air or alternatively the engine coolant as the cooling means. A charge air cooler is often provided for this purpose. In many cases, the dwell time of the air in the air ducts is often used as a means of improving the cooling effect. To this end, particularly where two turbochargers are used, the turbocharger on the right side may be used to exclusively charge the cylinders on the left side and vice versa, resulting in extended length of the air ducts and therefore cross over on their respective paths between the turbochargers and their respective cylinder banks.
It is also known to recirculate the exhaust gas, which is an effective way of reducing NOx emissions. This being the case, a part of the exhaust gas from the cylinders is recirculated into the fresh air delivery. To ensure that the exhaust gas is mixed with the fresh air as efficiently possible there, the proportion of exhaust gas is not introduced directly into the intake manifold of a cylinder bank and instead is introduced into the air ducts at a certain distance upstream. This provides a mixing run of a specific length.
The disadvantage of these known internal combustion engines, however, is that the layout of the two air ducts assigned to the respective cylinder banks requires a considerable amount of fitting space inside the engine compartment of the motor vehicle. One particular reason for this is the fact that these air ducts cross over and therefore have to be run past one another, which means that they require a proportion of the compartment volume that is at least more than double that of a single air duct. In addition, this configuration of the air ducts also means that the respective connectors to or the turbochargers on the cylinder banks are disposed in differing positions.
These problems are further exacerbated if an exhaust gas recirculation system is provided, requiring appropriate connecting lines to be accommodated in the engine compartment, but these are not of an identical design as a rule because they connect into the air ducts at mutually offset points.